1. Field of Invention
The present invention relates to a piezoelectric resonator device, a method for manufacturing the same, a ceramic package and a real time clock.
2. Description of Related Art
Currently, an IC chip and a quartz crystal oscillator are usually packaged in a hollow space formed on a ceramic package of a ceramic package type quartz oscillator. The ceramic package having a hollow space structure for housing these packaging members is usually used for a device for packaging an AT cut resonator element, and can include a laminated structure having three to five layers.
However, since a device provided with a tuning fork type piezoelectric resonator element is required to house the resonator element in vacuum, a cylinder type resonator is usually used for fixing the resonator in an evacuated cylinder. The resonator is constructed as a piezoelectric resonator device totally molded with a resin together with an IC chip for exciting the resonator. The molded resonator is shown in FIG. 6. In this structure, a tuning fork type resonator element 2 is packaged by housing in an evacuated cylinder 1, the cylinder 1 is disposed in adjoining relation to the IC chip 3, and the entire device is enclosed with a resin mold 4 while pulling out electrode terminals 5 out of the external sides thereof to manufacture a package.
Japanese Unexamined Utility Model Registration Application Publication No. 54-35870 is an example of the technical document related to the above technique.